Bacterial infection can lead to undesirable complications in particular during and directly after implanting an implantable device such as an artificial joint, i.e. an artificial knee, a hip prosthesis, a spinal implant or the like. Such infections usually are the result of contamination of implant surfaces due to adherence of bacteria and/or formation of biofilms. Once such contamination is present, up to now infection treatments usually require the use of antibiotics for example locally at the implant.
Even though the majority of developments addressing such problems are based on chemical approaches, developments exist making use of the application of electric fields. A typical prior art example is disclosed in document EP 0 346 058 B1. Therein a catheter is described including electrodes for applying electric fields across the catheter surfaces in order to reduce bacterial attachment. Therein, in particular the application of predominantly negative electrical fields is suggested.
Developments exist which focus on combining the effect of electrical fields with the use of medicine such as antibiotics. A typical prior art example is described in Document US 2010/0204551 A1. This document discloses an artificial knee implant wherein sensors including electrodes are provided at first and second joint portions, i.e. at femoral and tibial portions. Using the sensors connected to an external control device such as a personal computer, an infection can be detected and reported for example to a doctor. Once the infection is detected, according to this document it is suggested to apply local electric fields at a strength in between 0.2 kV/cm and 20 kV/cm to the electrodes for inducing electroporation of the bacterial cells. Due to the resulting increase of permeability of the cell membrane penetration of antibiotics, cytokines or other medicines is facilitated.
It is an object of the present invention to improve the state of the art by providing an artificial joint which allows prevention of infections and bacterial contamination of the implant surfaces. A further object is the provision of an artificial joint which allows reduction of bacterial adhesion to surfaces of the artificial joint and prevents the formation of biofilms, preferably before an infection is present. It is a further object of the present invention to provide an artificial joint which allows prevention of infections without the need for the use of medicine such as antibiotics. It is an even further object of the present invention to provide an artificial joint which allows prevention of infections while avoiding the use of large electric fields.
These and other objects which will become apparent upon reading the following description are solved by an artificial joint according to claim 1 and a system according to claim 15.